Automatic windshield wiper control systems that adjust wiper operation/speed to the presence of moisture or the intensity of rainfall on the windshield are well known in the art. Such systems typically include an electronic control module that is connected to the wiper arm drive motor. The control module adjusts the operation and speed of the wiper arm drive motor in response to sensory input.
For over 25 years, prior art automatic window wiper systems have either utilized optical sensors to detect the presence of moisture on the window or torque sensors to detect the resistance to the movement of the wiper blade across the window wherein that resistance has a tendency to decrease with increasing moisture. While these prior art systems have been largely effective for their intended purpose, further improvements in operation are possible.
This document relates to the first automatic window wiper system responsive to sensory input from both a window moisture sensor, such as an optical sensor, and a wiper torque sensor such as one incorporating a plurality of magnetoelastic bands carried on a pivot shaft extending between the wiper arm and the wiper drive motor and a plurality of field sensors that measure differences in magnetic field between the plurality of magnetoelastic bands.